Subscriptions to Request-Contained Resource Lists in the Session Initiation Protocol (SIP)This document specifies a way to create subscription to a list of resources in SIP. This is achieved by including the list of resources in the body of a SUBSCRIBE request. Instead of having a subscriber send a SUBSCRIBE request for each resource individually, the subscriber defines the resource list, subscribes to it, and gets notifications about changes in the resources' states using a single SUBSCRIBE dialog. [STANDARDS-TRACK]